/* ============================================================
   AI文物 · AIWENWU 设计系统
   视觉语言：深色科技底 + 文物金铜暖色 + AI 辉光/网格/粒子
   适配：PC 端 / 手机端（响应式）
   ============================================================ */

:root{
  --bg-0:#060912;
  --bg-1:#0a0f1e;
  --bg-2:#0f1628;
  --surface:rgba(255,255,255,.04);
  --surface-2:rgba(255,255,255,.07);
  --border:rgba(255,255,255,.10);
  --border-strong:rgba(255,255,255,.18);
  --txt:#e8edf7;
  --txt-dim:#9aa7c2;
  --txt-mute:#6b7894;
  --ai:#00e5ff;          /* AI 青 */
  --ai-2:#2d7dff;        /* 电蓝 */
  --ai-3:#7b5cff;        /* 紫 */
  --gold:#d8b15a;        /* 文物金 */
  --gold-2:#c8862f;      /* 陶铜 */
  --grad-ai:linear-gradient(135deg,#00e5ff 0%,#2d7dff 45%,#7b5cff 100%);
  --grad-gold:linear-gradient(135deg,#f4d68a 0%,#d8b15a 50%,#c8862f 100%);
  --glow-ai:0 0 24px rgba(0,229,255,.35);
  --glow-gold:0 0 24px rgba(216,177,90,.30);
  --radius:16px;
  --radius-sm:10px;
  --maxw:1240px;
  --font:"PingFang SC","Microsoft YaHei","Segoe UI",system-ui,-apple-system,sans-serif;
  --mono:"SFMono-Regular",Consolas,"Roboto Mono",monospace;
}

*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:var(--font);
  background:var(--bg-0);
  color:var(--txt);
  line-height:1.7;
  overflow-x:hidden;
  -webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{max-width:var(--maxw);margin:0 auto;padding:0 24px}
.mono{font-family:var(--mono)}
.hidden{display:none!important}

/* 背景网格 + 辉光 */
.bg-layer{position:fixed;inset:0;z-index:-2;pointer-events:none;
  background:
    radial-gradient(800px 600px at 80% -10%,rgba(45,125,255,.18),transparent 60%),
    radial-gradient(700px 500px at 10% 10%,rgba(0,229,255,.12),transparent 55%),
    radial-gradient(900px 700px at 50% 120%,rgba(123,92,255,.14),transparent 60%),
    var(--bg-0);
}
.bg-grid{position:fixed;inset:0;z-index:-1;pointer-events:none;opacity:.35;
  background-image:
    linear-gradient(rgba(255,255,255,.04) 1px,transparent 1px),
    linear-gradient(90deg,rgba(255,255,255,.04) 1px,transparent 1px);
  background-size:46px 46px;
  mask-image:radial-gradient(circle at 50% 30%,#000 0%,transparent 80%);
}
#particles{position:fixed;inset:0;z-index:-1;pointer-events:none;opacity:.5}

/* ---------------- 导航 ---------------- */
.site-header{position:sticky;top:0;z-index:100;
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  background:rgba(6,9,18,.72);border-bottom:1px solid var(--border)}
.nav{display:flex;align-items:center;justify-content:space-between;height:68px}
.brand{display:flex;align-items:center;gap:12px;font-weight:800;font-size:20px;letter-spacing:.5px}
.brand .logo{width:38px;height:38px;border-radius:10px;display:grid;place-items:center;
  background:var(--grad-ai);box-shadow:var(--glow-ai);font-size:20px;color:#04101e}
.brand .sub{font-size:11px;color:var(--txt-mute);font-weight:500;letter-spacing:2px;display:block;margin-top:-2px}
.nav-links{display:flex;gap:6px;align-items:center}
.nav-links a{padding:9px 14px;border-radius:10px;color:var(--txt-dim);font-size:15px;transition:.25s;position:relative}
.nav-links a:hover{color:var(--txt);background:var(--surface)}
.nav-links a.active{color:var(--ai)}
.nav-links a.active::after{content:"";position:absolute;left:14px;right:14px;bottom:4px;height:2px;background:var(--grad-ai);border-radius:2px}
.nav-cta{display:flex;gap:10px;align-items:center}
.btn{padding:10px 18px;border-radius:11px;font-size:14px;font-weight:600;cursor:pointer;border:1px solid var(--border-strong);transition:.25s;display:inline-flex;align-items:center;gap:8px;background:transparent;color:var(--txt)}
.btn:hover{transform:translateY(-2px);border-color:var(--ai)}
.btn-primary{background:var(--grad-ai);color:#04101e;border:none;box-shadow:var(--glow-ai)}
.btn-gold{background:var(--grad-gold);color:#2a1c05;border:none;box-shadow:var(--glow-gold)}
.btn-ghost{border-color:var(--border)}
.menu-toggle{display:none;background:none;border:none;color:var(--txt);font-size:26px;cursor:pointer}

/* ---------------- Hero ---------------- */
.hero{position:relative;padding:90px 0 70px;text-align:center;overflow:hidden}
.hero .tag{display:inline-flex;align-items:center;gap:8px;padding:7px 16px;border:1px solid var(--border-strong);
  border-radius:999px;font-size:13px;color:var(--txt-dim);background:var(--surface);margin-bottom:26px}
.hero .tag .dot{width:7px;height:7px;border-radius:50%;background:var(--ai);box-shadow:var(--glow-ai);animation:pulse 1.8s infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.3}}
.hero h1{font-size:clamp(34px,5.4vw,68px);line-height:1.1;font-weight:900;letter-spacing:1px;margin-bottom:22px}
.hero h1 .grad{background:var(--grad-ai);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero h1 .gold{background:var(--grad-gold);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p.lead{font-size:clamp(15px,1.8vw,19px);color:var(--txt-dim);max-width:760px;margin:0 auto 34px}
.hero-cta{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.hero-stats{display:flex;gap:36px;justify-content:center;flex-wrap:wrap;margin-top:56px}
.hero-stats .stat{text-align:center}
.hero-stats .num{font-size:clamp(26px,3.4vw,42px);font-weight:900;background:var(--grad-ai);-webkit-background-clip:text;background-clip:text;color:transparent;font-family:var(--mono)}
.hero-stats .lbl{font-size:13px;color:var(--txt-mute);margin-top:4px;letter-spacing:1px}

/* ---------------- 区块标题 ---------------- */
.section{padding:80px 0}
.section-head{text-align:center;max-width:760px;margin:0 auto 50px}
.section-head .kicker{font-family:var(--mono);font-size:13px;letter-spacing:3px;color:var(--ai);text-transform:uppercase;margin-bottom:12px;display:block}
.section-head h2{font-size:clamp(26px,3.4vw,42px);font-weight:900;margin-bottom:14px}
.section-head p{color:var(--txt-dim);font-size:16px}

/* ---------------- 卡片网格 ---------------- */
.grid{display:grid;gap:22px}
.grid-2{grid-template-columns:repeat(2,1fr)}
.grid-3{grid-template-columns:repeat(3,1fr)}
.grid-4{grid-template-columns:repeat(4,1fr)}

.card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:26px;
  transition:.3s;position:relative;overflow:hidden}
.card::before{content:"";position:absolute;inset:0;background:var(--grad-ai);opacity:0;transition:.3s;mix-blend-mode:overlay}
.card:hover{transform:translateY(-6px);border-color:var(--border-strong);box-shadow:0 18px 50px rgba(0,0,0,.45)}
.card:hover::before{opacity:.06}
.card .ic{width:52px;height:52px;border-radius:13px;display:grid;place-items:center;font-size:26px;
  background:var(--surface-2);border:1px solid var(--border);margin-bottom:18px;color:var(--ai)}
.card.gold .ic{color:var(--gold);border-color:rgba(216,177,90,.3)}
.card h3{font-size:19px;margin-bottom:10px;font-weight:700}
.card p{color:var(--txt-dim);font-size:14.5px}
.card .meta{margin-top:16px;font-size:12.5px;color:var(--txt-mute);font-family:var(--mono);display:flex;gap:10px;flex-wrap:wrap}
.card .meta span{border:1px solid var(--border);padding:3px 9px;border-radius:7px}

/* ---------------- 时间线（商业模式） ---------------- */
.timeline{position:relative;margin-top:20px;padding-left:8px}
.timeline::before{content:"";position:absolute;left:18px;top:6px;bottom:6px;width:2px;background:linear-gradient(var(--ai),var(--gold))}
.tl-item{position:relative;padding:0 0 34px 56px}
.tl-item .dot{position:absolute;left:9px;top:4px;width:20px;height:20px;border-radius:50%;background:var(--bg-1);border:2px solid var(--ai);box-shadow:var(--glow-ai)}
.tl-item h4{font-size:18px;margin-bottom:6px}
.tl-item p{color:var(--txt-dim);font-size:14.5px}

/* ---------------- 资讯列表 ---------------- */
.news-card{display:flex;gap:18px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:18px;transition:.25s}
.news-card:hover{transform:translateY(-3px);border-color:var(--border-strong)}
.news-card .thumb{width:140px;height:96px;border-radius:12px;flex-shrink:0;background:var(--grad-ai);display:grid;place-items:center;font-size:34px;color:#04101e}
.news-card .body h3{font-size:17px;margin-bottom:6px}
.news-card .body .date{font-size:12.5px;color:var(--ai);font-family:var(--mono);margin-bottom:8px}
.news-card .body p{color:var(--txt-dim);font-size:13.5px}

/* ---------------- 表单 ---------------- */
.form{display:grid;gap:16px;max-width:560px;margin:0 auto}
.field label{display:block;font-size:13px;color:var(--txt-dim);margin-bottom:7px}
.field input,.field textarea,.field select{width:100%;padding:12px 14px;border-radius:11px;background:var(--bg-2);
  border:1px solid var(--border);color:var(--txt);font-size:15px;font-family:var(--font);transition:.2s}
.field input:focus,.field textarea:focus{border-color:var(--ai);outline:none;box-shadow:var(--glow-ai)}

/* ---------------- 页脚 ---------------- */
.site-footer{border-top:1px solid var(--border);padding:54px 0 30px;margin-top:40px;background:rgba(10,15,30,.6)}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:30px}
.footer-grid h4{font-size:15px;margin-bottom:16px;color:var(--txt)}
.footer-grid a{display:block;color:var(--txt-dim);font-size:14px;padding:5px 0;transition:.2s}
.footer-grid a:hover{color:var(--ai)}
.footer-about p{color:var(--txt-dim);font-size:14px;max-width:340px;margin-top:14px}
.qr{width:108px;height:108px;border-radius:12px;background:var(--surface-2);border:1px solid var(--border);display:grid;place-items:center;font-size:12px;color:var(--txt-mute);text-align:center;padding:8px}
.footer-bottom{margin-top:36px;padding-top:22px;border-top:1px solid var(--border);display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;color:var(--txt-mute);font-size:13px}

/* ---------------- 通用工具 ---------------- */
.badge{display:inline-block;padding:4px 11px;border-radius:8px;font-size:12px;font-family:var(--mono);
  background:var(--surface-2);border:1px solid var(--border);color:var(--ai)}
.badge.gold{color:var(--gold);border-color:rgba(216,177,90,.3)}
.split{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:center}
.feature-list{list-style:none;display:grid;gap:14px}
.feature-list li{display:flex;gap:12px;align-items:flex-start;color:var(--txt-dim);font-size:15px}
.feature-list li .ck{color:var(--ai);font-weight:800;flex-shrink:0}
.glow-box{background:linear-gradient(135deg,rgba(0,229,255,.10),rgba(123,92,255,.10));border:1px solid var(--border-strong);border-radius:var(--radius);padding:30px}
.reveal{opacity:0;transform:translateY(26px);transition:.7s cubic-bezier(.2,.7,.2,1)}
.reveal.in{opacity:1;transform:none}

/* ---------------- 响应式 ---------------- */
@media(max-width:980px){
  .grid-4{grid-template-columns:repeat(2,1fr)}
  .grid-3{grid-template-columns:repeat(2,1fr)}
  .footer-grid{grid-template-columns:1fr 1fr}
  .split{grid-template-columns:1fr;gap:24px}
}
@media(max-width:760px){
  .nav-links{position:fixed;top:68px;left:0;right:0;background:rgba(6,9,18,.97);flex-direction:column;
    align-items:stretch;padding:14px 18px;gap:4px;border-bottom:1px solid var(--border);
    transform:translateY(-130%);transition:.3s;backdrop-filter:blur(14px)}
  .nav-links.open{transform:none}
  .nav-links a{padding:13px 10px}
  .menu-toggle{display:block}
  .nav-cta .btn-ghost{display:none}
  .grid-2,.grid-3,.grid-4{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
  .hero{padding:60px 0 40px}
  .section{padding:54px 0}
  .news-card{flex-direction:column}
  .news-card .thumb{width:100%;height:150px}
  .container{padding:0 18px}
}
@media(max-width:480px){
  .footer-grid{grid-template-columns:1fr}
  .hero-stats{gap:22px}
}